Core A. Administrative Core. This Core includes two parts: (1) an administrative component and (2) a component for biostatistics support of the Program. The administrative portion of this core is designed to provide fiscal management, to offer clerical and organizational support, to establish mechanisms for internal and external review of the Program (the latter via an external scientific advisory board), and to enhance the scientific interactions and collaborations among the Project and Core leaders. Fiscal management will include oversight of project and core budgets in accordance with policies and procedures of Yale University and the NIH, as well as oversight of staff appointments, salaries and fringe benefits, and other personnel issues. This core will also arrange meetings among Project and Core leaders, coordinate participation by Program faculty and staff in the Radiobiology Workshop and Journal Club series, and organize visits by the members of the board of externaladvisors. The adminsitrative core services are therefore essential for this Program to function as an effficient, cohesive unit. The biostatisticscomponent will provide all members of the Program with active consultation with qualified biostatisticians offering state-of-the-art methodology. These consultations will occur at all points of the research: from planning and design including sample size and power calculations to ongoing guidance during the data collection and support of manuscript writing for publication.